LR604 has been discontinued by ProChem and replaced by Black LR605. LR605 is C.I. reactive dye #5. I've just bought some and dyed some fabric at an 8% DOS and discovered it is not black at all, but blue.
When I looked at the data sheet for the old LR604, I discovered that is actually was a mix of CI reactive black #5 and CI reactive orange 107. I have used this ProChem branded remazol liquid for batik for years and have been so happy with it. I was able to get wonderful dark blacks and a wide range of greys with no weird separation of colors.
As far as I know, the old LR604 was the only nearly pure black out there. If anyone has suggestions for other single hue blacks, I'd appreciate it. I'll even consider a good premixed grey if someone really loves a mixture from ProChem. I guess my other alternative would be to try and mix my own grey.
Thanks in advance,